The classic Atiyah-Singer index theory of elliptic operators on compact manifolds has been vastly generalized to higher index theories of elliptic operators on noncompact spaces in the framework of noncommutative geometry [5] by Connes-Moscovici for covering spaces [8], Baum-Connes for spaces with proper and cocompact discrete group actions [2], Connes-Skandalis for foliated manifolds [9], and ...